CHAPTER 8 TRAFFIC CONTROL 8.1. … Works/right...pan, it is the center of the pan. City of...

City of Northglenn

Standards and Specifications

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CHAPTER 8 TRAFFIC CONTROL

8.1. INTRODUCTION

8.1.1 GENERAL

The standards contained in this chapter regulate all improvements and private work to be

dedicated to the public and accepted by the City and all work within the public right-of-way.

They are intended to provide for adequate, coordinated, modern development with required

facilities to serve and protect the potential users of the various areas of the community.

The standards in this chapter apply to new developments which are not constrained by already

existing improvements. This chapter is not to be applied without qualification to in-fill

development. In-fill development in an urban area is often constrained by existing

improvements. To the extent deemed possible by the City, in-fill developments shall be required

to conform to these STANDARDS AND SPECIFICATIONS. The City may allow modification

of these STANDARDS AND SPECIFICATIONS when necessary to allow private and public

construction which is compatible with surrounding in-place improvements.

8.1.2 GLOSSARY OF TERMS

AASHTO -- American Association of State Highway and Transportation Officials

Acceleration Lane -- A speed change lane, including tapered areas, for the purpose of enabling a

vehicle entering a roadway to increase its speed to a rate at which it can more safely merge with

through traffic.

Access -- Driveway or other point of access such as a street, road or highway that connects to the

general street system. Where two public roadways intersect, the secondary roadway shall be the

access.

Approach -- The portion of an intersection leg which is used by traffic approaching the

intersection.

Average Daily Traffic (ADT) -- The total bi-directional volume of traffic passing through a given

point during a given time period, divided by the number of days in that time period.

Band Width -- The time in seconds or the percent of cycle between a pair of parallel lines which

delineate progressive movement on a time-space diagram. It is a quantitative measurement of

through traffic capacity provided by signal progression.

Capacity -- The maximum number of vehicles that have a reasonable expectation of passing over

a given roadway or section of roadway in one direction during a given time period under

prevailing roadway and traffic conditions.

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Critical Volume -- A volume (or combination of volumes) for a given street which produces the

greatest utilization of capacity for that street in terms of passenger cars or mixed vehicles per

hour.

Cycle Time -- The time period in seconds required for one complete sequence of signal

indications.

Deceleration Lane -- A speed change lane, including tapered areas, for the purpose of enabling a

vehicle that is to make an exit turn from a roadway to slow to a safe turning speed after it has left

the main stream of faster-moving traffic.

Delay -- Stopped time per approach vehicle in seconds per vehicle.

Design Hour Volume (DHV) -- Hourly traffic volume used for street design and capacity

analysis, usually one or more peak hours during a twenty-four (24) hour period.

Design Speed -- Five to ten miles per hour (5-10 mph) above the proposed or desired speed limit

of the facility under design.

Design Vehicle -- Developments intended for public use must be designed for the following

types of vehicles:

Residential (excluding single-family or duplex) SU30

Commercial Uses WB40

Industrial Uses WB50

For public streets, the following design vehicles must be used:

Commercial/Multi-Family Locals & Minor Collectors SU30

Major Collectors WB40

Arterials WB50

Definitions for the above vehicle types are found in AASHTO Geometric Highway Design

Standards.

Divided Highway -- A highway with separated roadways for traffic in opposite directions, such

separation being indicated by depressed dividing strips, raised curbings, traffic islands, other

physical separations or by standard pavement markings and other traffic control devices.

Fire Trucks -- Must be considered as a WB40 truck with a minimum forty-five-foot (45') radius

for design purposes and any other requirements as determined by local fire protection district.

Flowline -- The transition point between the gutter and the face of the curb. For a cross or valley

pan, it is the center of the pan.

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Grade -- Rate or percent of slope, either ascending or descending from or along the highway. It

is usually measured along the centerline of the highway or access.

Green Time -- The length of a green phase plus its change interval, in seconds.

Hourly Volume -- The number of (mixed) vehicles that pass over a given section of a lane or

roadway during a time period of one (1) hour.

Level of Service (LOS) -- A measure of the mobility characteristics of an intersection as

determined by vehicle delay and a secondary factor, the volume/capacity ratio.

MUTCD -- Manual on Uniform Traffic Control Devices and the Colorado Supplement.

Sight Distance -- The length of roadway ahead visible to the driver. The minimum sight distance

available should be sufficiently long to enable a vehicle traveling at or near the design speed to

stop before reaching a stationary object in its path.

Signal Progression -- Progressive movement of traffic at a planned rate of speed through adjacent

signalized locations within a traffic control system without stopping.

Speed Change Lane -- A separate lane for the purpose of enabling a vehicle entering or leaving a

roadway to increase (acceleration lane) or decrease (deceleration lane) its speed to a rate at

which it can more safely merge or diverge with through traffic.

Stopping Sight Distance -- The distance traveled by the vehicle from the instant the driver of a

vehicle sights an object necessitating a stop to the instant the brakes are applied and the distance

required to stop the vehicle from the instant brake application begins.

Storage Lane -- Additional lane footage added to a deceleration lane to store the maximum

number of vehicles likely to accumulate during a critical period without interfering with the

through lanes.

Time Space Diagram -- A chart on which the distance between signals and signal timing is

plotted against time. The chart, when completed, indicates signal progression band widths and

speed of traffic.

8.2. DESIGN STANDARDS

8.2.1 RESPONSIBILITIES FOR TRAFFIC STUDIES

Traffic studies may be required by the City in order to adequately assess the impacts of a

development proposal on the existing and/or planned street system. The primary responsibility

for assessing the traffic impacts associated with a proposed development shall rest with the

developer, with the City serving in a review capacity.

Unless waived by the Public Works Director, a written study meeting the criteria contained in

this chapter shall be required for a development proposal when trip generation during the AM or

PM peak hour is expected to exceed one hundred (100) vehicles, as determined by the Public

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Works Director. This study shall be the responsibility of the applicant and shall be prepared by a

Professional Engineer registered in the State of Colorado, with adequate experience in

transportation engineering. Upon submission of a draft traffic study, the Public Works Director

will review the study data sources, methods and findings. Comments shall be provided in a

written form. The developer and the project engineer will then have an opportunity to

incorporate necessary revisions prior to submitting a final report. All studies shall be approved

by the Public Works Director before acceptance. The following submittals may require traffic

studies:

A. A rezoning application or an application for annexation into the City.

B. A preliminary map or final plat if the property has already been rezoned for

the proposed use and no traffic study was required for the rezoning, or the

land use assumptions at the time of platting will result in trip generation

increasing by more than fifteen percent (15%) compared to trip generation

estimates made for the traffic study at the time of rezoning.

C. Prior to issuance of a building permit, if the property has already been

zoned/platted and no previous traffic study less than two (2) years old

exists.

D. The applicant shall be required to submit a new traffic study if, after

submitting the original traffic study for any of the above submittals, the trip

generation is increased by more than fifteen percent (15%) or the land use

is changed so that trip generation is increased by more than fifteen percent

(15%).

All previous traffic studies relating to the development that are more than two (2) years old shall

be updated, unless the Public Works Director determines that conditions have not changed

significantly. Where access points are not defined or a site plan is not available at the time the

traffic study is prepared, additional traffic analysis may be required when a site plan becomes

available or the access points are defined.

The applicant will be notified at the pre-planning stage if a traffic study will be required,

provided sufficient information is available for the City to determine whether the trip generation

criterion has been met. If insufficient information is available but the property appears to involve

a sufficiently intense land use, the applicant will be informed that a traffic study is required.

Transportation consultants are required to discuss projects with the Public Works Director prior

to starting the study. As a minimum, topics for possible discussion at such meeting shall include

trip generation, directional distribution of traffic, trip assignment, definition of the study area,

intersections requiring capacity/level of service analysis and methods for projecting build-out

volume. This will provide a firm base of cooperation and communication between the City, the

owner or developer and the project's consultants in forecasting future traffic characteristics

which realistically define traffic movement associated with the proposed development. Specific

requirements will vary depending on the site location.

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8.2.2 TRAFFIC STUDY FORMAT

In order to provide consistency and to facilitate staff review of traffic studies, the following

format shall be followed in the preparation of such studies by transportation consultants.

8.2.2.1. Introduction:

The introduction portion of the report must contain the following:

a. A note stating the following: “We acknowledge that the City

of Northglenn’s review of this study is only for general

conformance with submittal requirements, current design

criteria and standard engineering principles and practices.”

b. A brief description of the size of the land parcel, general

terrain features, the location within the jurisdiction and the

region shall be included in this section. In addition, the

roadways that afford access to the site and are included in the

study area shall be identified. The exact limits of the study

area should be based on engineering judgment and an

understanding of existing traffic conditions surrounding the

site. In all instances, however, the study area limits shall be

mutually agreed upon by the developer, his engineer and the

Public Works Director. A vicinity map that shows the site

and the study area boundaries in relation to the surrounding

transportation system shall be included.

c. The existing and proposed uses of the site shall be identified

in terms of the various zoning categories of the City. In

addition, the specific use for which the request is being made

shall be identified, if known, since a number of uses may be

permitted under the existing ordinances. It shall be the intent

of the traffic study to evaluate the worst case traffic impacts

for the proposed development allowed by the zoning. If

several different uses are permitted by the zoning, the highest

trip generation shall be assumed for the study.

d. A complete description (including a map) of the existing land

uses in the study area, as well as their current zoning and use,

shall be included. In addition, all vacant land within the

study area and its assumed future uses shall be identified.

This latter item is especially important where large tracts of

undeveloped land are in the vicinity of the site and within the

prescribed study area. Generally, much of this information

can be obtained from the City's Planning Division staff.

e. Within the study area, the applicant shall describe and

provide volumes for existing roadways and intersections,

including geometrics and traffic signal control, as well as

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improvements contemplated by all affected government

agencies. This would include the nature of the improvement

project, its extent, implementation schedule, and the agency

or funding source responsible. A map shall be provided

showing the location of such facilities.

8.2.2.2. Trip Generation and Design Hour Volumes:

A summary table listing each type of land use, the size involved, the average trip

generation rates used (total daily traffic and a.m./p.m. peaks) and the resultant total trips

generated shall be provided. Trip generation shall be calculated for the maximum uses

allowed under the existing and proposed zoning based on the latest data contained within

the Institute of Transportation Engineers (ITE) Trip Generation Manual; or other

applicable sources. In the event that data is not available for the proposed land use, the

City must approve estimated rates prior to acceptance. The calculation of design hour

volumes used to determine study area impacts shall be based on:

a. Peak hour trip generation rates as published in the ITE Trip

Generation Summary or other applicable sources.

b. Traffic volume counts for similar existing uses if no

published rates are available.

c. Additional sources from other jurisdictions, if acceptable to

the Public Works Director.

Use of reduction factors to account for passerby traffic may be considered upon approval

of the Public Works Director. Internal trip reductions and modal split assumptions will

require analytical support to demonstrate how the figures were derived and will require

approval by the Public Works Director.

8.2.2.3. Trip Distribution:

The estimates of percentage distribution of trips from the proposed development to

destinations in the metro region shall be clearly stated in the report using the north,

south, east and west compass points. Market studies and information concerning origin

of trip attractions to the proposed development may be used to support these assumptions

where available. A map showing the percentage of site traffic on each street shall be

provided as part of the traffic study graphic material.

8.2.2.4. Trip Assignment:

The direction of approach of site-generated traffic via the area's street system shall be

presented in this section. The technical analysis steps, basic methods and assumptions

used in this work shall be clearly stated and agreed to by the Public Works Director. The

assumed trip distribution and assignment shall represent the most logically traveled

routes for drivers accessing the proposed development. These routes can be determined

by observation of travel patterns to existing land uses in the study area.

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8.2.2.5. Existing and Project Traffic Volumes:

Graphics shall be provided which show the following traffic impacts for private access

points, public intersections, and public streets.

a. A.M. peak-hour site traffic (in and out), including turning

movements.

b. P.M. peak-hour site traffic (in and out), including turning

movements.

c. A.M. peak-hour total traffic (in and out), including

site-generated traffic. These volumes must include through

and turning movement volumes for current conditions and

separate set of numbers that also include twenty (20) year

projections or build-out, whichever is specified by the Public

Works Director.

d. P.M. peak-hour total traffic (in and out), including

site-generated traffic. These volumes shall include through

and turning movement volumes for current conditions and a

separate set of numbers that also include twenty (20) year

projections or build-out, whichever is specified by the Public

Works Director.

e. Any other peak hour which may be critical to site traffic and

the street system in the study area should be included in the

graphics and show the same information as is provided for

the a.m./p.m. peak hours.

f. Actual counts of existing total daily traffic for the street

system in the study area at the time the study is being

prepared.

g. Projected total daily traffic for the street system in the study

area based on traffic from the proposed development and

counts of existing daily traffic obtained in Item “f” above.

The component of the existing daily traffic attributable to the

existing uses shall be identified and the increase in total daily

traffic from the proposed uses.

h. Projected total daily traffic for the street system in the study

area based on traffic from the proposed development, counts

of existing daily traffic obtained in Item “f” above, traffic

projections based on build-out of land use within the study

area, or a twenty (20) year projection, whichever is specified

by the Public Works Director.

All raw traffic count data, including average daily volumes and peak-hour turning

movements and analysis worksheets shall be provided in the appendices of the report.

Computer techniques and the associated printouts may be used as part of the report.

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Volume projections for background traffic growth will be provided by the Public Works

Director or alternatively, a method for determining these volumes will be recommended

by the Public Works Director. All total daily traffic counts shall be actual machine

counts and not based on factored peak-hour sampling. Latest available machine counts

from the Colorado Department of Transportation, the City and other agencies may be

acceptable if not more than two (2) years old.

8.2.2.6. Level of Service:

Level of Service "C" shall be the design objective for all movements, and under no

circumstances will less than level of Service "D" be accepted for site and non-site traffic,

including existing traffic at build-out of the study area. The design year will be

approximately twenty (20) years following construction and include volumes generated

by build-out of the study area or a twenty (20) year projection in background traffic,

whichever is specified by the Public Works Director. The following interpretations of

"Level of Service" have been provided:

Level of Service A. A condition of free flow with low-traffic density where no vehicle

waits longer than one (1) signal cycle.

Level of Service B. A stable flow of traffic where only on a rare occasion do drivers

wait through more than one (1) signal cycle.

Level of Service C. Still in the zone of stable flow but intermittently, drivers must wait

through more than one (1) signal cycle and back-ups may develop behind left-turning

vehicles.

Level of Service D. Approaching instability, drivers are restricted in their freedom to

change lanes and delays for approaching vehicles may be substantial during peak hours.

Level of Service E. Traffic volumes are near or at the capacity of the arterial and long

queues of vehicles may create lengthy delays, especially for left-turning vehicles.

Level of Service F. Congested condition of forced traffic flow where queued back-ups

from locations downstream restrict or prevent movement of vehicles out of the approach

creating a storage area during part or all of the peak hour.

8.2.2.7. Capacity Analysis:

A capacity analysis shall be conducted for all public street intersections impacted by the

proposed development and for all private property access points to streets adjacent to the

proposed development and within the limits of the previously defined study area. The

a.m., p.m., and any other possible peak period shall be tested to determine which peak

hours need to be analyzed. Capacity calculations should also include an analysis for the

twenty- (20) year projections or study area build-out conditions. The capacity analysis

calculations should be based on the latest approved techniques as published in the latest

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update of TRB Special Report 209. All capacity analysis worksheets shall be included in

the appendices of the report.

8.2.2.8. Traffic Signals:

The need for new traffic signals shall be based on warrants contained in the Manual on

Uniform Traffic Control Devices and any additional warrants established by the National

Committee on Uniform Traffic Control Devices. In determining the location of a new

signal, traffic progression is important. Generally, a spacing of one-half (1/2) mile for all

signalized intersections should be maintained. This spacing is desirable to achieve good

speed, capacity and optimum signal progression. Pedestrian movements shall be

considered in the evaluation and adequate pedestrian clearance provided in the signal

cycle split assumptions.

To provide flexibility for existing conditions and ensure optimum two-way signal

progression, an approved traffic engineering analysis shall be made to properly locate all

proposed accesses that may require signalization. The section of roadway to be analyzed

for signal progression will be determined by the City and will include all existing and

possible future signalized intersections.

The progression pattern calculations shall use a cycle consistent with current

signal-timing policies of the City. A desirable band width of fifty percent (50%) of the

signal cycle shall be used where existing conditions allow. Where intersections have no

signals presently but are expected to have signals, typically a sixty percent (60%)

mainline, forty percent (40%) cross-street cycle split should be assumed. Cycle split

assumptions shall relate to volume assumptions in the capacity analysis of individual

intersections, and where computerized progression analysis techniques are used they

shall be the type which utilize turning-movement volume data and pedestrian clearance

times in the development of time/space diagrams. The green time allocated to the cross

street shall be considered no less than the time which is required for a pedestrian to clear

the main street using the Manual on Uniform Traffic Control Devices standards. Those

intersections which would reduce the optimum ban width if a traffic signal were installed

may be required by the City to remain unsignalized and have turning movements limited

by access design or median islands.

8.2.2.9. Traffic Accidents:

Traffic accident data for affected street corridors may be required for the study. The

study period will normally be three (3) years. Such locations will be specified by the

Public Works Director. Where this is necessary, estimates of increased or decreased

accident potential shall be evaluated for the development, particularly if the proposed

development might impact existing traffic safety problems in the study area and safety

improvements recommended where necessary.

8.2.2.10. Noise Attenuation:

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If a residential development is planned adjacent to a freeway or arterial roadway, the

need for noise attenuation measures may be required as part of the impact analysis. It is

recommended that the need for noise attenuation measures be determined using the

methods outlined in Colorado Department of Transportation Noise Analysis and

Abatement Guidelines, Latest Edition.

8.2.2.11. Recommendations:

In the event that analysis indicates unsatisfactory levels of service on study area

roadways, a description of proposed improvements to remedy deficiencies shall be

included. These proposals would include projects by the City or the Colorado

Department of Transportation for which funds have been appropriated and obligated.

The assumptions regarding all existing and future roads in an analysis will require

approval from the Public Works Director. In general, the recommendation section

should include:

a. Proposed Recommended Improvements. This section must

describe the location, nature and extent of proposed

improvements to assure sufficient roadway capacity. A

sketch of each improvement should be provided showing the

length, width and other pertinent geometric features of the

proposed improvements.

b. Level of Service Capacity Analysis at Critical Points.

Another iteration of the operational analysis shall be

described which demonstrates the anticipated level of service

as a result of making these improvements. This level of

service must be "D" or better.

c. Traffic Volume Proportions. Percentages based on the traffic

impact analysis may be required by the City to determine the

proportion of traffic using various public improvements (both

existing and proposed) from several developments within the

study area.

Conclusions:

This last section of the report must be a clear, concise description of the study findings

explained in a manner that a citizen could understand as the language in this section will

be inserted into the Planning Commission and City Council agenda memorandums. At

minimum, the summary will include information pertaining to existing site generated

traffic, impacts and mitigation measures and when they will be implemented.

8.2.2.12. Revisions to Traffic Study:

Revisions to the traffic study shall be provided as required by the Public Works Director.

The need to require revisions will be based on the completeness of the traffic study, the

thoroughness of the impact evaluation and the compatibility of the study with the

proposed access and development plan.

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8.2.2.13. Summary of Typical Study Contents

a. Introduction:

1) Land Use, Site and Study Area Boundaries (provide

map)

2) Existing and Proposed Site Uses and Circulation

(provide map)

3) Existing and Proposed Uses in Vicinity of Site

(provide map)

4) Existing and Proposed Roadway and Intersections

(provide map)

b. Trip Generation and Design Hour Volumes (provide table)

c. Trip Distribution (provide figure)

d. Trip Assignment (provide figure)

e. Existing and Projected Traffic Volumes (provide figure for

each item):

1) A.M. Peak Hour Site Traffic (including turning

movements)

2) P.M. Peak Hour Site Traffic (including turning

movements)

3) A.M. Peak Hour Total Traffic (including

site-generated traffic and projected traffic)

4) P.M. Peak Hour Total Traffic (including

site-generated traffic and projected traffic)

5) Any Other Peak Hour Necessary for Complete

Analysis

6) Total Daily Existing Traffic for Street System in

Study Area


Study Area and New Site Traffic


Study Area plus New Site Traffic and Projected

Traffic from Build-Out of Study Area Land Uses

f. Level of Service

g. Capacity Analysis (provide analysis sheets in appendices)

h. Traffic Signals (provide analysis sheets in appendices)

i. Traffic Accidents (optional) (provide collision diagrams and

accident rates)

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j. Noise Attenuation

k. Conclusions

l. Recommendations:

1) Proposed Recommended Improvements (provide

sketches of improvements)

2) Volume/Capacity Analysis at Critical Points

(provide analysis sheets in appendices

3) Traffic Volume Proportions

NOTE: Information required on figures may be combined provided that the

information is clearly legible.

8.2.3 ACCESS REQUIREMENTS AND CRITERIA

8.2.3.1. General

New access to City streets and roadways is approved through one of the two

mechanisms:

a. For new developments, access is granted through the

Planning Commission approval of the Final Development

Plan; Planned Unit Development (PUD) or subdivision plat.

b. To obtain access to City streets from existing developed

property, the mechanism is dependent upon zoning.

For property classified as a standard zoning district (other than Planned Unit

Development), the application should be made to the Planning and Development

Department and accompanied by plans of the proposed access and technical justification

for the access and associated public improvements.

For Planned Unit Developments, new or altered access shall be obtained through the

Planned Unit Development (PUD) amendment process. This involves applying through

the Planning and Development Department for an amendment to the appropriate PUD.

The application should be accompanied by appropriate plans for the proposed access and

technical justification, including justification for the extent of the improvements

proposed at the access point.

The Planning and Development Staff is available to provide advice on the extent of

technical justification required for any access request. It is recommended that this advice

be sought prior to submitting any application.

8.2.3.2. State Highways

a. Access to state highways is governed by the State Highway

Access Code.

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b. The City of Northglenn has delegated its authority to

administer the State Highway Access Code to the Colorado

Department of Transportation who is, therefore, responsible

for the review of issuance of access permits to State

Highways in the City of Northglenn.

8.2.3.3. Arterials

a. A right of way permit shall be obtained from the Public

Works Department for any public or private access

constructed in the City’s Right of Way.

b. Private, direct access to arterials shall be permitted only:

1) When the property in question has no other

reasonable access to the general street system; or

2) When denial of direct access to the arterial and

alternative direct access to another roadway would

cause unacceptable traffic operation and safety

problems to the overall traffic flow of the general

street system.

c. When direct private access must be provided, the following

shall be considered:

1) Such access shall continue only until such time that

some other reasonable access to a lower function

category street is available and permitted. The right

of way permit should specify the future reasonable

access location(s), if known, and under what

circumstances what changes will be required.

2) No more than one (1) access shall be provided to an

individual parcel or to contiguous parcels under the

same ownership unless it can be shown that allowing

only one access conflicts with safety regulations (i.e.;

fire access) or if additional access would

significantly benefit safety and operation of the

Arterial and is necessary to the safe and efficient use

of the property.

3) An access shall be limited to right turns only unless

it has the potential for signalization, left turns would

not create unreasonable congestion or safety

problems and lower the level of service, or if

alternatives to the left turns would not cause

unacceptable traffic operation and safety problems to

the general street system.

d. Public direct access to arterial where left turns are to be

permitted shall meet the signal-spacing criteria of this

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chapter. Those that do not meet these requirements shall be

limited to right turns only, unless they meet the requirements

mentioned above. No local streets shall be permitted to

intersect arterials.

e. Spacing and Signalization:

1) In general terms, full access to arterials shall be

limited to one-half (1/2) mile intervals, plus or minus

approximately two hundred feet (200'), in order to

achieve good speed, capacity and optional signal

progression.

2) To provide flexibility for both existing and future

conditions, an approved engineering analysis of

signal progression shall be made to properly locate

any proposed access that may require signalization.

8.2.3.4. Collectors

Private access to collectors shall be governed by the following curb opening and

driveway criteria. Single-family residence access to collectors is not permitted. Public

streets shall intersect collectors not closer than three hundred and thirty feet (330') from

each other (centerline to centerline).

8.2.3.5. Local Streets

Private access to local streets shall be governed by the following curb opening and

driveway criteria.

Public streets should not intersect local roadways closer than one hundred and fifty feet

(150') from each other (centerline to centerline).

8.2.3.6. Basic Principles for Curb Openings and Driveways

Certain control values for curb openings and driveways require minimum dimensions in

some instances and maximum values for other dimensions. The design of curb openings

and driveways within the range of these dimensions will provide for good service on the

part of the motorist using the driveway while at the same time minimizing the

interference to the traffic using the street. By controlling the location and width of

openings of driveways along the street, it will be possible to avoid or eliminate long,

open stretches where motorists can indiscriminately drive onto the street. The width of

opening established in these STANDARDS AND SPECIFICATIONS are based on

studies which indicate that the various width openings will accommodate vehicles of

maximum size authorized on City streets.

The opening or driveway width should be adequate to handle properly the anticipated

traffic volume and character of traffic, as well as being within the limits specified for the

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type of property development. The controls established for curb openings and driveways

shall apply to existing streets as well as new streets that may be developed in the future.

To the greatest extent possible, all openings for driveways shall be located at the point of

optimum sight distance along the street. For openings and driveways to commercial

establishments and service stations, there shall be sufficient space reasonably cleared of

any obstructions such that drivers entering the property will have sufficient sight distance

to enable them to make proper and safe movements. The profile of a driveway approach

and the grading of the adjacent area shall be such that when a vehicle is located on the

driveway outside the traveled portion of street the driver can see a sufficient distance in

both directions to enable him to enter the street without creating a hazardous traffic

situation.

Any adjustments which must be made to utility poles, street light standards, fire

hydrants, catch basins or intakes, traffic signs and signals or other public improvements

or installations which are necessary as the result of the curb openings or driveways shall

be accomplished without any cost to the City of Northglenn. Also, any curb opening or

driveway which has been abandoned shall be restored by the property owner except

where such abandonment has been made at the request of or for the convenience of the

City.

Driveway approaches, whereby the driveway is to serve as an entrance only or as an exit

only, shall be appropriately signed by and at the expense of the property owner. The

property owner will be required to provide some means of ensuring that the motorists

will use the driveway either as an entrance only or an exit only, but not both.

8.2.3.7. Definition of Terms

Several terms are used herein which have a somewhat distinct meaning. For the purpose

of clarity, the definition of some of these terms are listed below:

a. Width of Curb Opening (W) -- The width of curb opening

measured at the curb line.

b. Edge Clearance (E) -- The distance measured along curb line

from the nearest edge of the curb opening to a point where

the property line extended intersects the curb line.

c. Corner Clearance (C) -- At an intersecting street, the distance

measured along the curb line from the projection of the

intersection street right-of-way line to the nearest edge of the

curb opening.

d. Distance Between Double Drives (D) -- The distance

measured along the curb line between the inside edges of two

adjacent curb openings.

e. Setback (S) -- The lateral distance measured perpendicular to

the street right-of-way line and extending from the

right-of-way line to the closest point on a structure.

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f. Frontage -- The distance along the street right-of-way line of

a single property or development within the property lines.

Corner property at an intersection would have a separate

frontage along each street.

g. Residential -- Property used primarily for residential

purposes such as single-family, two-family, and multi-family

units.

1) Single-Family (SF) Residential: Single, detached

family dwelling units, double bungalows, or

duplexes.

2) Multi-Family (MF) Residential: Three or more

attached dwelling units including townhouses,

condominiums, and apartments.

h. Commercial -- Establishments where the buying and selling

of commodities, entertainment or services is carried on,

excluding service stations. Included are such uses as office

buildings, restaurants, hotels, motels, banks, grocery stores,

theaters, parking lots, trailer courts and public buildings.

i. Service Station -- Any property where flammable liquids

such as motor vehicle fuel are used, stored and/or dispensed

from fixed equipment into fuel tanks of motor vehicles.

j. Industrial or Warehouse -- Any establishment that

manufactures or stores an article or product.

k. Radius Curb Returns -- The curved portion of a street curb at

street intersections or the curved portion of a curb in the end

slopes of a driveway approach.

8.2.3.8. General Requirements

8.2.3.8.1 Number of Openings

Single-Family Residential -

In general, each single-family residential property shall be

limited to one (1) access point.

Multi-Family Residential -

In general, access shall be determined by information

provided by the owner/developer in the traffic impact study

and by comments generated during the Public Works

Director's review and acceptance of that study.

Commercial -

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In general, commercial property having less than one hundred

and fifty feet (150') of frontage and located mid-block shall

be limited to one (1) access point to the street. An exception

to this rule may be where a building is constructed in the

middle of a lot and parking is provided for on each side of the

building. A second access point may be allowed for

commercial property having more than one hundred fifty feet

(150') of frontage. For commercial property located on a

corner, one (1) access to each street may be permitted.

Service Stations -

Where there is sufficient frontage to provide for minimum

and maximum requirements, two (2) access points to a street

may be permitted.

Industrial -

Access shall be determined on a case-by-case basis. The City

shall consider good traffic engineering practice and the

information provided by the applicant in the traffic impact

study accompanying the submittal.

8.2.3.9. Amount of Curb Opening Permitted

The total length of curb opening on a street for access to a commercial property or

service station shall not exceed thirty-five feet (35'). This requirement does not apply to

residential-type curb openings.

8.2.3.10. Entrance Angle:

In general, the entrance angle for all driveway approaches shall be as near ninety degrees

(90o) to the centerline of the street as possible. The minimum angle which will be

permitted is sixty degrees (60o).

8.2.3.11. Minimum Space Between Openings:

The minimum spacing between curb openings shall be thirty-five feet (35') measured at

the curb line. This spacing shall apply to double drives that serve a single property, as

well as the distance between drives serving adjoining properties. A fifty-foot (50')

spacing applies to commercial openings.

8.2.3.12. Joint Entrances:

Whenever possible and feasible, joint entrances shall be provided to serve two adjacent

properties. Joint entrances are to be centered on the common property line.

8.2.4 CONTROL DIMENSIONS

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To accomplish the objectives of the basic principles stated earlier, certain control dimensions are

necessary. There are many variables which affect these control dimensions. Some of the

variables are as follows: type of street classification, type of private property development,

volume and type of traffic and width of right-of-way.

8.2.4.1. Width of Curb Opening (W)

The total width of curb opening for properties on various function street classifications

shall be in conformance with the detail drawings in the Appendix of these

STANDARDS AND SPECIFICATIONS.

Curb openings of thirty-five feet (35') or more shall be constructed as radius curb returns.

8.2.4.1.1 Residential.

No edge clearance is required for residential access. However, the drive

shall not extend beyond the property line extended.

8.2.4.1.2 Commercial.

Access onto an Arterial -- 75 Feet Minimum

Access onto a Local -- 75 Feet Minimum

NOTE: Joint access with adjoining property is encouraged. Joint access shall be the

only justification for reducing the minimum edge clearance dimension.

8.2.4.1.3 Service Stations.

Access onto an Arterial -- 5 Feet Minimum

Access onto a Local -- 5 Feet Minimum

8.2.4.2. Corner Clearance:

It is important to locate driveways away from major intersections. This constraint is as

much for the ability to enter and leave the property as for the benefit of intersection

safety and operations. Exiting a driveway during peak-hour conditions at traffic signals

is difficult where the queue of standing or slow-moving vehicles never allows a

sufficient gap for entry from the driveway.

8.2.4.3. Sight Distance:

Sight distance for curb openings to private property shall be in accordance with Chapter

7 and 8 of these STANDARDS AND SPECIFICATIONS.

8.3. STREET LIGHTING

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8.3.1 STREET LIGHTING PROCEDURE

The developer shall submit a written request for street light design to the relevant power

authority. The relevant power authority will submit the final design and cost estimates to the

Public Works Director for review and approval. Developer will pay the relevant power authority

the total costs of installation for all street lighting within the prescribed time period. Developer

will be responsible for street lighting within the development as well as on side streets

surrounding the development site.

8.4. PARKING

8.4.1 PARKING

Parking layout dimensions are provided in the Municipal Code. Other angled parking layouts

meeting the approval of the Public Works Director will be permitted where possible.

8.4.2 MAXIMUM ALLOWABLE GRADES PERMITTED IN PARKING LOTS

Maximum grades permitted in parking lots must not exceed eight percent (8%).

8.4.3 HANDICAPPED PARKING POSTING

In general, each handicapped parking stall should be between twelve feet (12’) and fourteen feet

(14') in width, must have a stall depth of at least eighteen feet (18'), and be located near buildings

and handicap ramps. However, handicap parking design must conform to the latest Americans

with Disabilities Act guidelines. A handicapped parking space will be required to be identified

by an official "Handicapped Reserve Parking" (Manual on Uniform Traffic Control Devices,

R7-8) sign with the handicapped person logo.

In order for handicapped parking spaces to function as intended, they will be required to be

designed and signed in a uniform manner to allow for a clear understanding of the parking zone

and to make enforcement possible. Signing of one, two, or three spaces for handicapped parking

spaces must be done by using one sign for each space placed at the center of each end line.

8.4.4 PARKING STRUCTURES

For design details and optimum layout of parking structures, reference to Parking Garage

Planning and Operation, by the Eno Foundation for Transportation, Inc., (Latest Edition), or the

Urban Land Institute Standards is recommended. The City will evaluate designs for such

structures on an individual case basis.

8.5. CONSTRUCTION STANDARDS

8.5.1 TRAFFIC SIGNALS

8.5.1.1. General Requirements

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The work specified in this section describes the installation of necessary material and

equipment to complete traffic signals and/or other electrical systems as specified on the

drawings, in the special contract provisions, or herein. All traffic signals shall be

designed by a Professional Engineer registered in the State of Colorado.

8.5.1.2. Traffic Control and Street Closure

The contractor will be required to maintain access to all private drives throughout the

period of construction for this project. The contractor shall be required to erect and

maintain all barricades, traffic control signs, cones and other traffic control items

necessary to provide proper traffic control during construction. The contractor shall

submit three (3) copies of the traffic control plan to the Public Works Director for

approval 72 hours prior to beginning construction. At the completion of the project the

contractor shall remove all barricades, traffic control signs, cones and other necessary

construction traffic control items and return all areas or permanent traffic control devices

damaged during construction to their original condition at no cost to the City. Traffic

control signs and devices shall be in accordance with "Manual on Uniform Traffic

Control Devices for Streets and Highways", Latest Edition, published by the Federal

Highway Administration, and as directed by the Engineer.

8.5.1.3. Testing

The City may at its option and cost retain the services of an independent testing lab to

perform all testing consultation and to assist in the review of the work and equipment.

8.5.1.4. Intersection Power

The contractor shall notify the engineer three (3) weeks prior to the signal turn-on so that

orders may be issued for power connection to the intersection on the specified turn-on

date.

8.5.1.5. Equipment Salvage

All traffic signal equipment that is deemed salvageable by the City which is removed

shall remain the property of the City. Such property is to be removed from the work site

and returned by the contractor to the City of Northglenn Public Works Department.

8.5.1.6. Existing Traffic Signals

When existing traffic signal installations are modified or completely rebuilt, the

contractor shall avoid disturbing existing traffic signal equipment until the new or

modified traffic signal system has been installed and put into operation. If the existing

traffic signal equipment must be removed to accommodate the new construction, the

contractor shall, with the engineer's approval and at the contractor’s sole expense, install

temporary overhead traffic signal equipment. The contractor shall at all times maintain a

minimum of two (2) three-section (red, yellow, and green) traffic signal heads for each

roadway approach.

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8.5.1.7. Signal Heads

Signal heads installed on standards or poles at new signal locations which are not ready

for actual electrical operation shall be bagged.

8.5.1.8. Field Location

All loops, poles, control cabinets, pull box locations and pole foundations shall be field

located by the engineer. Traffic signal poles and mast arms shall not be ordered until

field verification of pole foundations is complete.

8.5.1.9. Utilities

All utilities shall be shown on the maps to the extent that they can, based upon utility

records, surface field indications and proposed installations. During the progress of the

work, all utility locations and elevations will necessarily require field verification in

cooperation with the affected companies and public agencies. The contractor shall be

responsible for locating all valve boxes, manholes, etc., and insuring that they are

properly protected and/or adjusted.

8.5.1.10. Notification of Work

The contractor shall work only on weekdays as set forth in approved Right of Way

permits. The contractor must receive written approval from the engineer to work at any

other time.

8.5.1.11. Regulations and Code

All electrical equipment and material shall conform to the standards of the National

Electrical Manufacturers Association (NEMA) the Colorado State Highway Department,

whichever is applicable. In addition to requirements of these specifications, the plans,

the special contract provisions, all material and work shall conform to the requirements

of the National Electrical Code (hereinafter referred to as the "Code"), the Rules for

Overhead Electrical Line Construction of the Public Utilities Commission, the Standards

of the American Society for Testing Materials (ASTM), the American Standards

Association (ASA) and any local ordinance which may apply. Wherever reference is

made in these specifications or in the special contract provisions to the code, rules or the

standards mentioned above, the reference shall be construed to mean the code, rule or

standard that is in effect at the date of bidding.

8.5.1.12. Equipment list and Drawings

The contractor shall submit a list of equipment and material which he proposes to furnish

within five days of the execution of the owner-contractor agreement. The submittal shall

including all equipment and material as identified on the plans or in the specifications by

the manufacturer's name which is necessary or customary in the trade to identify such

equipment and material. The list shall be complete as to name of manufacturer, unit size,

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material composition and shall be supplemented by such other data as may be required

by the Public Works Director.

Inspection or sampling of any materials, other than those already approved, according to

the material specifications must be made by the engineer or his designee prior to

installation. If the contractor proposes a substitution of equipment called for in the plans

or specifications, he shall provide additional information to prove the substitution item is

of equal or superior quality. Any material and/or equipment installed by the contractor

that is not in conformance with the City of Northglenn specifications will be removed or

changed at the contractor's expense. Upon completion of the work, the contractor shall

submit an "as-built" or corrected plan showing, in detail, all construction changes

including, but not limited to, wiring, cable and location and depth of conduit.

8.5.1.13. Excavating and Backfill

Excavations for the installation of conduit, foundations and other traffic signal items

shall be performed in such a manner as to cause the least possible injury to the streets,

sidewalks and other improvements. The trenches shall not be excavated wider than

necessary for the proper installation of the electrical appliances and foundations.

Excavating shall not be performed until immediately before installation of conduit and

other appliances. The material from the excavation shall be removed as the trenching

progresses.

Trenches in existing or proposed roadways shall be backfilled with concrete or approved

flow-fill material. After backfilling all trenches shall be kept well filled and maintained

in a smooth and well-drained condition until permanent repairs are made.

Excavations in streets or highways shall be performed in such a manner that one (1) lane

of traffic in each direction shall be open to public traffic. All lane closures shall be

approved by engineer prior to closure. At the end of each day's work and any other time

construction operations are suspended, all construction equipment and other obstructions

shall be removed from that portion of the roadway open for use by public traffic. When

excavations must remain open overnight, they shall be properly marked to warn

motorists and/or pedestrians according to guidelines established in the "Manual on

Uniform Traffic Control Devices for Streets and Highways” latest edition.

8.5.1.14. Removing and Replacing Improvements

The contractor shall at his sole expense, replace or reconstruct sidewalks, curbs, gutters,

rigid or flexible pavement and any other City or privately owned property which is

removed, broken or damaged by him with material which conforms to current City

STANDARDS AND SPECIFICATIONS. Whenever a part of a square or slab or

existing concrete, sidewalk, or driveway is broken or damaged, the entire square or slab

shall be removed and the concrete reconstructed.

The outline of all areas to be removed in Portland cement concrete sidewalks and in

pavements shall be cut to a minimum depth of one-and-one-half inches (1-1/2") with an

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abrasive type saw prior to removing the sidewalk and pavement material. Cut for

remainder of the required depth may be made by a method satisfactory to the engineer.

Cuts shall be neat and true with no shatter outside the removal area.

8.5.2 UNDERGROUND FACILITIES

8.5.2.1. Foundations

a. All foundations shall be Portland cement concrete

conforming to the applicable requirements of construction

specifications of the City of Northglenn, except as herein

provided.

b. The bottom of concrete foundations shall rest on firm ground.

Cast-in-place foundations shall be poured monolithically

where practicable. The exposed portions shall be formed to

present a neat appearance.

c. Forms shall be true to line and grade. Tops of foundations,

except as noted on plans, shall be finished to curb or

sidewalk grade or as ordered by the engineer. Forms shall be

rigid and securely braced in place and inspected prior to the

pouring of concrete. Conduit ends and anchor bolts shall be

placed in proper position and in a template until the concrete

sets.

d. Anchor bolts shall conform to the specifications and each

individual bolt shall have two (2) flat washers, one (1) lock

washer and two (2) nuts. Shims or other similar devices for

plumbing or raking will not be permitted.

e. Both forms and ground which will be in contact with the

concrete shall be moistened before placing concrete. Forms

shall not be removed until the concrete has thoroughly set.

f. All abandoned foundations shall be removed and disposed of

by the contractor. All conduit runs associated with an

abandoned foundation shall be extended or abandoned as

called for on the plans. When a foundation is removed, the

hole shall be backfilled in accordance with State of Colorado

and City of Northglenn standard practices.

8.5.2.2. Conduit

a. All cables and conductors not shown on the plans as aerial

cable shall be installed in conduit unless installed in poles,

pedestals or mast arms. All metal conduit referred to in the

specifications and shown on the plans shall be rigid and

adequately galvanized. All PVC conduit will be of Schedule

80 or greater.

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b. All trenches excavated in roadways, including new

construction areas, shall be backfilled with concrete or State

of Colorado approved flow fill, and capped with six inches

(6") of Grade E Asphaltic Pavement.

c. Table 8.1 includes the conduit schedule.

Table 8.1 - Conduit Schedule

Run Type Quantity Size (Inches) Use

Street Crossings 1 3 120 voltage

Street Crossings 1 2 Low voltage

Street Crossings 1 2 Xcel use

Signal Pole 1 3 Signal cables

Signal Pole 1 2 Xcel use

Controller Cabinet 2 3 120 voltage

Controller Cabinet 2 2 Low voltage

Interconnect 1 2 Interconnect

Service Point 1 2 Xcel use

d. The contractor, at his sole expense, may use larger conduit if

desired. Where larger conduit is used, it shall be for the entire

length of the run from outlet. No reducing couplings will be

permitted underground.

e. The end of all metal conduit, existing or new, shall be well

reamed to remove burrs and rough edges. Field cuts of

existing or new conduit shall be made square and true, and

the ends shall butt together for the full circumference thereof.

Slip joints of running thread will not be permitted for

coupling metal conduit. When a standard coupling cannot be

used, an approved threaded union coupling shall be used. All

couplings shall be screwed up until the ends of the metal

conduits are brought together.

f. Where a "stub out" is called for on the plans, a sweeping ell

shall be installed in the direction indicated and properly

capped. The locations of ends of all conduits in structures or

terminating at curbs shall be marked by a "Y" at least three

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inches (3") high cut into the face of the curb, gutter, or wall

directly above the conduit.

g. Conduit bends, except factory bends, shall have a radius of

not less than six (6) times the inside diameter of the conduit.

Where factory bends are not used, conduit shall be bent

without crimping or flattening, using the longest radius

practicable.

h. Conduit shall be laid at a depth of not less than twenty-four

inches (24") below the top of curb grade in sidewalk or grass

areas and to a depth of not less than thirty inches (30") below

the finished grade in all other areas. Conduit under railroad

tracks shall be not less than forty-eight inches (48') below the

bottom of the tie.

i. Trench excavations for conduit shall be two inches (2") wider

than the outside diameter of the conduit. Backfilling of

conduit trenches shall be accomplished by placing concrete

or approved flow-fill up to the bottom surface of the existing

or new roadway surface material. The remaining portion of

the excavation shall be backfilled with the same type of

material used to construct the existing roadway surface.

j. Conduit shall always enter a foundation, pull box or any

other type structure from the direction of the run only.

k. Conduits terminating in a pole shall extend approximately

two inches (2") vertically above the foundation.

l. All conduit runs that exceed ten feet (10') in length shall have

a continuous nylon line pulled into the conduit along with the

specified electrical cables. The line shall be firmly secured at

each end of the conduit run with a minimum slack of three

feet (3'). The purpose of this line is to be able to pull future

electrical cable through the existing conduit runs.

m. Existing underground conduit to be incorporated into a new

system shall be cleaned with a mandrel or blown out with

compressed air.

n. Install a #12 locate wire inside the conduit throughout the

length of the installation

o. New conduit runs shown on the plans are for bidding

purposes only and may be changed with approval of the

Public Works Director or designee. The City may request the

installation of spare conduits.

8.5.2.3. Pull Boxes

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a. Pull box shall always be installed in combination with a steel

strain pole and at all other locations shown on the plans and

at such additional points as ordered by the engineer. The

contractor may install, at his own expense, any additional

pull box that he may desire to facilitate the work.

b. Special pull boxes which are required shall be fabricated and

installed in general conformance with the size and details

shown on standard drawings.

c. Pull boxes installed in concrete or similar finished areas shall

be designed for such installations and shall be stackable and

manufactured of a Precast polymer concrete material such as

Quazite or an approved equal. Unless otherwise noted, pull

box lids shall have the word “Traffic” cast into them. Pull

boxes shall be installed so that the covers are level with curb

or sidewalk grade or level with the surrounding ground when

no grade is established. The bottoms of all pull boxes shall

be bedded in crushed rock.

d. When a new conduit run enters an existing pull box, the

contractor shall remove the pull box or tunnel under the side

at no less than eighteen inches (18") and enter from the

direction of the run. No new conduit will be allowed to enter

a new or existing pull box in any other manner than that

shown on standard drawings.

e. Loop detector pull boxes installed in the street shall be placed

according to the plans or as directed by the Public Works

Director or designee. The lids shall have the word "Traffic"

cast into them.

8.5.2.4. Detector Loop Wire Installation

a. The use of detector loops instead of cameras must be

approved by the Public Works Director. If approved, each

individual detector loop is to be terminated within a water

valve housing as specified on the construction drawing, and

each loop shall consist of one continuous wire, without

splicing, to this termination point. Any required series or

parallel connections are to be at the termination point.

b. All loops shall have a tag attached to the leading clockwise

lead of the loop. This tag shall be marked to indicate the

relative location of the loop. This marking shall correspond

directly to the loop designations on the intersection drawing

provided in the contract.

c. Detector loop roadway slots shall be cut in asphalt that has a

6 inch minimum depth and sealed one-fourth inch (1/4")

below the surface level of the roadway with 3M or approved

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equal. This sealer is to be used whether or not the roadway is

to be overlaid.

d. The contractor shall include cost for loop wire, saw cutting,

sealant, splice and test for a complete installation of the loop

to the termination point for the pay item price.

8.5.2.5. Conductor and Cable

a. Wiring shall conform to appropriate articles of the National

Electric Code. Wiring within cabinets, junction boxes, etc.,

shall be neatly arranged.

b. Powdered soap stone, talc or other approved lubricant shall

be used in placing conductors in conduit.

c. A common neutral conductor, separate from the signal light

circuit neutral, shall be used for all low-voltage circuits,

including the detectors and pedestrian push-button circuits.

d. Splicing of cable will not be permitted in conduit or pull

boxes or outside of signal heads, standards or foundations.

e. In no case shall any shellac compounds be used. Wire nut

type connectors shall be used on all splices made above

ground level. Detector loop lead-in splices in underground

systems shall be waterproofed with 3M splice kits or City

approved equivalent. A minimum of twelve inches (12") of

slack shall be left at each splice except within hand-holes

where twenty-four inches (24") shall be left.

f. When conductors and cables are pulled into the conduit, all

ends of conductors and cables shall be taped to exclude

moisture and shall be so kept until the splices are made or

terminal appliances attached. Ends of spare conductors shall

be taped and marked.

g. Cable shall be stranded. For span wire type installations,

cable shall be installed where specified on the plans and

secured to messenger cable with cable rings in accordance

with standard practices. Aerial cable shall be supported by

strand vices of proper size and strength as well as insulators

used where necessary.

h. A small permanent tag on which the direction and phase is

printed, in the order named, using the codes given in "Cable

Schedule," shall be securely attached near the end of each

conductor at each controller, standard, or pull box where

conductors are separated. Where direction and phase are not

clearly indicated by conductor insulation, additional tags

shall be used.

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Table 8.2 - Cable Schedule

Phase/Tag Tape Color

1. NBLT Red/White

2. NB Red

3. SBLT Green/White

4. SB Green

5. EBLT Orange/White

6. EB Orange

7. WBLT Blue/White

8. WB Blue

9. Pedestrian Yellow

NOTE: This is a typical cable schedule and shall be used for the

wiring of all signal installations. A new cable schedule will be

noted on the plans at each intersection where different phasing

and/or special equipment is required. It should be noted that a

band of white is used to indicate a left turn and yellow for a

pedestrian movement. This is in addition to directional tape for

the phase. For cable size and number of conductors see traffic

signal material specifications and/or standard drawings.

i. Inboard and outboard heads, mounted on mast arms, are to be

wired separately from head to base of pole. Seven conductor

for outbound and side-of-pole signal heads required.

8.5.2.6. Bonding and Grounding

a. Metallic cable sheaths, conduit, metal poles and foundations

shall be made mechanically and electrically secure to form a

continuous system and shall be effectively grounded.

Bonding and grounding jumpers shall be copper wire, No. 8

AWG, for all systems. Beldon cable sheath for loop

detectors to be grounded in control cabinet only. The other

end of the sheath to be left ungrounded.

b. Bonding of standards shall be by means of a bonding wire

attached to a bolt or a three-sixteenths inch (3/16") or larger

bolt installed in the lower portion of the shaft.

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c. At each pull box the ground electrode shall be a one-piece

copper ground rod of five-eighths inch (5/8") diameter and

eight feet (8') in length, driven into the ground so that the top

is two inches (2") above the bottom of the pull box. The

ground rod connector will be placed so that the bare copper

wire, No. 8, can be pulled into a pole, foundation, or attached

to the control cabinet ground buss.

8.5.2.7. Maintenance

The contractor shall have full maintenance responsibility of the traffic signal from the

date of the written notification by the Public Works Director to the final inspection and

date of written approval of the work performed. Continuous maintenance and

emergency service shall be provided by the Contractor 24 hours each day during the time

frame outlined above. The Contractor shall provide and maintain a 24-hour a day

continuous one number telephone answering service. All malfunctions of a controller

and its accessory equipment shall be considered an emergency unless otherwise

identified by the City. Equipment malfunctions and/or damage, which in the opinion of

Northglenn's Transportation Engineer or other authorized person, constitutes a serious

hazard or inconvenience to the public shall be considered an emergency. Such

malfunctions or damage may include, but not necessarily be limited to, situations where:

a. all indications are out including bulbs and lenses, for any one

traffic movement;

b. signal heads give conflicting indications to any intersection

approach;

c. a signal has been knocked down;

d. an overhead red indication is out

Contractor shall undertake each such emergency repair no later than one hour after

Northglenn notifies Contractor of the emergency.

In instances of repairs that are not of an emergency nature, such repairs shall be

undertaken at the site within one working day after Northglenn notifies Contractor of the

needed repair. Northglenn shall pay the Contractor for the materials, parts and/or

supplies actually used by the Contractor in making any such repair in the amount of the

Contractor's cost plus five percent (5%). Labor and equipment rates associated with

work performed due to vandalism or vehicle accident damage will be reimbursed at the

rate set forth in the City's Traffic Signal Maintenance Contract.

Should the Contractor fail to perform any maintenance responsibilities within the

prescribed time periods, the Public Works Director or other authorized person shall

employ the services of the City's designated Traffic Signal Maintenance Contractor to

perform said maintenance work. The Contractor shall reimburse the City for labor and

equipment charges associated with the utilization of the City's designated Traffic Signal

Maintenance Contractor plus a fifteen percent (15%) administration fee.

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8.5.2.8. Field Testing

Prior to completion of the work, the contractor shall cause the following tests to be made

on all traffic signals in the presence of the engineer or his designee.

a. Each circuit shall be tested for continuity.

b. Each circuit shall be tested for grounds.

c. A functional test shall be made in which it is demonstrated

that each and every part of the system functions as specified

or intended herein. The functional test for each traffic signal

system shall consist of not less than fourteen (14) days of

continuous, satisfactory operation commencing with full

operation of all electrical facilities. During the fourteen-day

period, the contractor will maintain the system or systems.

The cost of any maintenance necessary, except electrical

energy and maintenance due to damage by public traffic,

shall be borne by the contractor and will be considered as

included in the price paid for the contract item involved and

no additional compensation will be allowed.

8.5.3 TRAFFIC CONTROL IN CONSTRUCTION AREAS

8.5.3.1. General

For any construction done on, in or to an existing City roadway and/or right-of-way or

for the construction of a new City roadway, appropriate traffic control during

construction shall be provided. For any such construction, a construction traffic control

plan shall be prepared by the contractor and/or project engineer and shall be approved by

the Public Works Director prior to issuance of a right-of-way permit.

Where a roadway does not currently exist, it is presumed that there is no motorist

expectation of a travel route. Therefore, a construction traffic control plan for

construction of a new roadway should strive to do two things: alert the motorist that this

is a construction area, and alert the motorist that the road is not open to traffic.

Construction traffic control plans shall also be prepared for construction occurring on

existing City roadways where the motorist has an expectation of accessibility and shall

be warned, advised, guided or regulated through any construction activity.

8.5.3.2. Time of Submittal

A construction traffic control plan shall be submitted to the Public Works Director at the

earliest with the submittal of final construction plans and at the latest with the

application for a right-of-way or public improvement construction permit(s). All final

construction plans submitted to the City of Northglenn that entail constriction on an

existing City roadway or construction of a new City roadway must either:

a. Be accompanied by a construction traffic control plan.

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b. Include a note stating a construction traffic control plan shall

be submitted to the City of Northglenn for approval before

any permit for construction is issued. No right-of-way or

public improvement construction permit shall be issued

without the approved construction traffic control plan.

8.5.3.3. Scope of Construction Traffic Control Plan

For construction of new roadways, traffic control during construction should strive to

keep the motorist from entering the facility. The primary means to accomplish this are

by use of temporary barricades located in advance of the point where new construction

joins old and appropriate signing. New roadways shall not be opened to general traffic,

nor the construction traffic controls remove, without the approval of the Engineering

Construction Inspector and the Public Works Director. One precondition of such an

opening is that permanent signage and striping be in place.

8.5.3.4. Elements of Construction Traffic Control Plan

a. All construction traffic control plans shall contain the

following information:

1) Name of contracting firm and, if different, the name

of the firm responsible for traffic control devices.

2) Name and phone number(s) of 24-hour contact

person responsible for traffic control devices.

3) Description of location of activity (roadway names,

north arrow, etc.)

b. Projects identified as minor construction traffic control plans

as determined by the Public Works Director shall include, in

addition to items listed in (A) above, either one of the

following:

1) A neat sketch of the roadways and the proposed

traffic control devices; or

2) A copy of a typical drawing of traffic device layout

from an accepted source approved by the City’s

Transportation Engineer.

c. Projects identified as major construction traffic control plans

as determined by the Public Works Director shall include, in

addition to items in (A) above, the following: The proposed

traffic control devices specifically identified as to type and

explicitly noted and dimensioned on as-builts, construction

plan drawings or other detailed drawings.

8.5.3.5. Basis for Construction Traffic Control Plan

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The Manual on Uniform Traffic Control Devices shall be the basis upon which the

traffic control plan is designed in concert with proper, prudent and safe engineering

practice. All necessary signing, striping, coning, barricading, flagging, etc. shall be

shown on the plan. Other acceptable documents may be consulted or referenced, such as

Traffic Control in Construction and Maintenance Work Zone (FHWA) and the Flagging

and Traffic Control Supervisor’s Training Manual (CDOT).

8.5.3.6. Restriction, Regulations and Opportunities

In concept, City streets shall not be closed overnight and work shall not force road or

lane closures before 8:30 a.m. or after 3:30 p.m for arterials and collectors. Residential

streets shall not be closed overnight and work shall not force road or lane closures before

8:30 a.m. or after 5:30 p.m. If exceptions to this are required, this shall be noted on the

construction traffic control plan and shall be approved by the Public Works Director.

Travelway width may be restricted. Minimum travel lane width in construction areas

shall be ten feet (10’), but proper controls, including flagging, shall be indicated.

Prohibition of on-street parking should be considered and noted where applicable.

All traffic control devices necessary to provide for public safety at the work site shall be

furnished and maintained by the contractor at his own expense. If the contractor does not

provide the approved traffic control devices, the Public Works Director may install such

devices and the entire costs of such devices shall be borne by contractor.

8.5.3.7. Approval

Staff of the City’s Public Works Department must approve (sign and date) all

construction traffic control plans. All complete road closures and all partial road

closures (removing one or more travel lanes) that are proposed for overnight shall be

approved by the Public Works Director. One (1) copy of the approved plan shall remain

with the Public Works Department for their verification that the traffic control plan has

been adhered to in the field. One (1) copy shall be placed in the engineering project file.

The contractor shall have one (1) approved copy of the traffic control plan on site at all

times.

8.5.3.8. Modifications

Actual conditions in the field may necessitate modifications to the construction traffic

control plan. Provided that the general intent of the original plan is satisfied, these

modifications may occur without revision to the plan. The Engineering Construction

Inspector shall be notified of any substantial changes and may refer these to the Public

Works Department as needed for construction.

8.5.3.9. Applicability

The requirements of this chapter shall apply to any person, corporation, municipality,

quasi-municipality agencies, mutual companies, electric, gas or communication utility

(including cable TV) who for any reason cuts, disturbs or otherwise defaces any City

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road for the purposes of installing or repairing or for any reason pertaining to the

presence of an underground utility or structure.

8.5.4 TRAFFIC SIGNING AND PAVEMENT MARKINGS

8.5.4.1. General

The installation of all traffic control devices shall conform to the Manual on Uniform

Traffic Control Devices and the Colorado Standard Specifications for Road and Bridge

Construction, latest edition.

8.5.4.2. Traffic Control Devices on Public Property

All permanently fixed traffic signals will generally be installed by the City at the

developer’s expense. However, if the developer submits a signage plan which is

subsequently approved by the Public Works Director, the developer may install these

traffic signs. Traffic signs shall be placed to conform to the drawing details.

8.5.4.3. Traffic Control Devices on Private Property

a. Responsibility: All traffic control devices on private

property; i.e., pavement markings, regulatory signs, fire lane

signs and handicapped parking signs shall be installed and

maintained by the property owner.

b. Placement: A signage and striping plan specifying the

various types and combinations of traffic control devices

shall be submitted to the Public Works Director for approval.

8.5.4.4. Pavement Markings

All Pavement Markings required to be installed as a result of new construction or

development shall be THERMOPLASTIC as per CDOT specifications. Temporary

pavement markings necessary to facilitate construction (i.e. detours) may be installed

using paint.

The contractor shall submit a plan for all pavement markings to the Public Works

Director for approval prior to the beginning of the work. The pavement marking plan

shall meet the requirements for such work as outlined in the Manual on Uniform Traffic

Control Devices. All pavement marking materials must be approved by the Public

Works Director.

8.6. MATERIAL SPECIFICATIONS

8.6.1 SIGNAL HEADS

8.6.1.1. Traffic Signal Unit Specifications

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a. All signal units shall be of the individual section, adjustable

type, black polycarbonate or approved equivalent. Unless

otherwise noted on the plans, all signal and pedestrian

displays shall be ITE approved Light Emitting Diodes (LED)

and conform to the appropriate sections below. All

southbound overhead red and southbound overhead red-

arrows shall be incandescent type and conform to sections B

through F below.

b. Visors shall be detachable, of the twelve-inch (12") tunnel

type, open at the bottom; be black in color on the outside and

flat black on the inside.

c. Reflectors shall be silvered glass or Alzak type units.

d. Lenses shall be in accordance with Institute of Traffic

Engineers Specifications.

e. Sockets shall be fixed focus.

f. Doors on the signal heads for the installation of lamps and

lens replacement or other maintenance shall not require use

of any tool whatsoever to be opened. Doors and lenses shall

be equipped with neoprene weatherproof gaskets to ensure

against infiltration of moisture, road film and dust. Each

three-color signal unit shall have the socket leads from all

signal sections connected to a terminal board stamped with

identifiable terminals. There shall be a terminal for color

indication plus a common terminal where one lead from each

socket shall terminate. The terminal board shall be mounted

in the middle section and be properly insulated. All

openings, top and bottom, shall be for one-half-inch (1/2")

pipe or pipe mounting brackets. Gaskets shall be supplied for

top and bottom openings.

8.6.1.2. Pedestrian Signal Units

Sixteen-inch (16"), one-way, ICC or equal countdown with audible chirp pedestrian

signal head as specified on the plans. "Walk/Don't Walk" indications shall be

symbolized and side by side. Visors shall be egg crate type and heads shall be black.

8.6.1.3. Backplates

a. Where shown on the plans, black back plates shall be

furnished and installed on signal faces. No background light

shall show between the back plates and the signal face or

between sections. All back plates are to be of aluminum or

plastic construction and shall be the louvered type. Back

plates shall provide a five-inch (5") border for all twelve-inch

(12") signal heads.

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b. Traffic signal heads requiring backboards shall be drilled for

three-sixteenths-inch diameter by one-half-inch (3/16" x

1/2") pan head bolt with nut and lock washer. If the

manufacturer fails to supply as described, it will then be the

contractor's responsibility to do so. When installing

backboards on the traffic signal head, the contractor will

furnish three-sixteenths-inch (3/16") fender washers between

bolt head and backboard

c. The manufacturer will fabricate all backboards with a

three-sixteenths-inch (3/16") washer on both sides of each

rivet which is used to hold each section of backboard

together.

8.6.1.4. Traffic Signal Lamps

a. Traffic signal lamps shall meet the requirements of the latest

version of the ITE Standard "Traffic Signal Lamps." All

lamps shall have 8,000-hour minimum rating. Lamp

manufacturers shall be limited to General Electric, Sylvania,

Phillips. Size of lamps to be used in traffic signal units shall

be as follows:

b. 69 watt, 125 volt, lamps for all peds.

c. 150 watt or 1950 lumens minimum, 125 volt, lamps for all

twelve-inch (12") traffic signals.

d. If the manufacturer recommends a lower rating, the City of

Northglenn will be advised of this recommendation and will

have the option to decide which rating will be used.

8.6.2 ELECTRICAL CABLE

8.6.2.1. Signal Cable

14 AWG multi-conductor, stranded, copper wire manufactured to meet IMSA 19-1

specifications or approved equivalent. Each conductor in the cable will be individually

insulated and rated at 600 volts. There shall be a minimum of four (4) and a maximum

of nine (9) strands per conductor. There shall be a separate 19-conductor cable installed

from the controller cabinet to the bottom handhold of each signal pole. From that point,

a separate 5 or 7-conductor cable for each overhead signal shall be spliced to the 19-

conductor cable.

8.6.2.2. Interconnect Cable

a. At locations specified by the Public Works Director or where

multiple traffic signals are to be constructed in close

proximity, interconnection of the traffic signals through

copper interconnect may be required. The telephone

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hardwire interconnect wire shall be #19 AWG, 6 twisted

pairs, shielded cable, with petrolatum-polyethylene gel filling

compound. The cable shall meet R. E. A. Specification

PE-39 (Clifford of Vermont Catalog #6P19-B1-BJFC or

approved equal).

b. No splicing of the interconnect cable will be allowed. The

cable shall be installed between two adjacent controller

cabinets in continuous runs.

c. All telephone interconnect cable pairs will be connected to

either active or spare terminal points provided in the

controller cabinet. The Contractor shall identify and label all

terminal points.

d. All interconnect wires shall be checked after installation to

determine their resistance and resistance to ground. Each

pair shall be shorted together at one end and a resistance

check will be made at the other end or wherever a splice

exists. Resistance will be checked between each conductor

and ground. All resistance readings shall be recorded

showing value, color and location or wire. Data is to be

supplied to the City's Public Works Department within 30

days of completion of the project.

At the terminal points, the jackets shall be stripped and the ends taped. Gel filling

compound shall be removed using filled cable cleaner.

8.6.2.3. Service Cable

Two (2) No. TRW-8, seven (7) strands, tinned, soft-drawn copper wire,

one-sixteenth-inch (1/16") neoprene insulation, black and white in color.

8.6.2.4. Loop Wire

Detect-A-Duct Cable consisting of single conductor No. 14, stranded THHN with an

outer protective sleeve.

8.6.2.5. Pedestrian Push-Button Cable

Two (2) conductor No. 14, seven (7) strands, tinned, soft-drawn copper wire,

one-sixteenth-inch (1/16") neoprene insulation. Conductors to be twisted. Color coded

one (1) white and one (1) black.

8.6.2.6. Loop Lead-In Cable

Detector loop lead-in cable shall be a four conductor .25 inch diameter, shielded and

jacketed cable suitable for installation in a pavement sawslot, conduit or direct burial.

Conductors shall be AWG No. 18 stranded copper with polypropylene insulation. The

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conductors shall be twisted at least six turns per foot. Color rotation shall be black, red,

white, green. The interior of the cable shall be filled with an amorphous material which

prevents water penetration. Aluminized polyester shielding shall be applied around the

conductors to prevent electromagnetic interference. The Cable jacket shall consist of

black high density polyethylene. The jacket shall not be degraded by prolonged

exposure to typical pavement runoff components. The cable shall be suitable for

operation at temperatures of -60oC to +80oC. (Canoga 30003 43#18 AWG shielded

loop detector lead-in cable or approved equal.)

8.6.2.7. Ground

Single conductor, AWG No. 8, soft-drawn bare copper wire.

8.6.2.8. Optical Detector Lead-In Cable

The lead-in cable for the Emergency Vehicle Optical Detectors shall be GTT Type 138

or approved equal.

8.6.3 VEHICLE DETECTORS

8.6.3.1. General

a. Unless otherwise noted, all traffic signal vehicle detection

systems shall be accomplished through a video camera

system. All camera systems shall be 100 percent compatible

with the City’s existing equipment. The remaining portions

of this section reference roadway imbedded inductive loop

systems and are applicable when specified. This

specification defines the minimum design operational and

performance requirements for multiple channel, digital

self-tuning inductive loop detectors, detector units shall be

card rack mounted plug-in type and operate from an external

24 VDC power supply. Detector units shall be in full

compliance with the environmental and size requirements of

NEMA standard TS1-Section 15 and meet the design,

operation, electrical and functional performance requirements

of both TS1 and TS2 specifications.

b. The front panel shall include an erasable, write-on channel

identification area and clearly indicated switch operating

position. I.D. area one centimeter square per channel

minimum.

c. All component part and test points shall be clearly identified

by permanent marking of circuit referenced on the P. C.

Board. Integrated circuit devices having 16 or more leads

shall be socket-mounted to facilitate repair and maintenance

of units. Detectors supplied to this specification shall be

warranted by the supplier to be free of defects in materials

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and workmanship for a period of five years from date of

shipment from manufacturer.

d. Each detector unit shall include two or four complete

detector channels. Each channel shall sequentially energize

its loop inputs to eliminate crosstalk (mutual coupling)

between large, very closely spaced adjacent loops connected

to the same unit. The sequential time sharing and digital

processing of loop inductance data shall be accomplished on

a single LSI microcircuit per unit for maximum reliability.

The method of measuring shall be crystal reference digital

period counting, multi-channel scanning. Only one channel

input per unit shall be active at any point in time.

1) Sequential scanning shall fully prevent crosstalk

between channels of a detector connected to closely

spaced or overlapped loops for directional detection.

2) Sequential scanning shall allow two detection

channels to operate with full performance using a

common home-run cable.

3) Sequential scanning shall allow two or more

detection channels to be connected to a single

detection amplifier with full operating performance,

including separate mode and sensitivity selection

capability on each channel.

e. Each channel of the sensor unit shall automatically self tune

to any loop and lead-in inductance from 20 to 2500

microhenries within 2 seconds with full sensitivity after

application or interruption of supply voltage. Units shall also

track changes in loop/lead-in electrical characteristics, as

might reasonably be expected to occur in undamaged loops,

properly installed in sound pavements, without producing

false indications or changes in sensitivity.

f. Each detector unit shall be provided with a loop test switch

position to verify loop system integrity and reduce

maintenance costs. The "open loop test" position shall

indicate a previous fault via the front panel indicator. The

memory shall remain intact and can be queried repeatedly.

Existing detections shall not be reset and the memory shall

only be reset by power interruption as by removing and

re-inserting the plug-in detector units.

g. Each channel shall include a 16-position Push type wheel

switch to allow selection of 8 pulse sensitivities, 7 presence

levels and a "Reset" and an "Off" position. Each detector

unit shall include 8 sensitivity selections in 2:1 steps that can

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be correlated to the relationship of the number of turns of

wire in a loop versus the sensitivity required to detect a

specified vehicle. The selections shall be designed to allow

detection of licensable vehicles in loops of two or more turns

electrically in series, parallel or series/parallel configuration

in non-reinforced or reinforced pavements with

lead-in/homerun combinations from 50-feet to 1000-feet.

The number of turns in a loop, electrical configuration of

multiple loops and pavement type will dictate the sensitivity

required for proper, predictable detection.

h. If specified, channel presence time shall be modified if delay

or extension time is selected. The timing switch shall select

delay or extension or "Off", if no timing is desired. Internal

DIP switches shall provide for selection of "Delay" time of 0

to 31 seconds in 1.0 second increments and "Extension" time

of 0 to 7-3/4 seconds in .25 second increments.

i. Presence indicators shall be wide angle, high brightness type

Led's suitable for sunlight visibility. When timing is selected

and a channel is active that channel's indicator shall flash at 4

Hz during Delay and at 16 Hz during Extension to indicate

timing is in progress. Further, the timing shall be aborted

when the vehicle is no longer present and/or the channel

control input shall become inactive. The Delay timer shall be

reset when a vehicle leaves the loop prior to time out and

shall abort when the control input becomes inactive. The

Extension timer shall operate and reset when a vehicle leaves

the loop and be aborted when the control input becomes

inactive. Each timer (Delay and Extension) shall be provided

with buffer circuitry to enable or disable the timer based on

an external input (green gate) signal. Circuit shall be

designed for AC or DC input control on AC powered units

and for DC control on DC powered units.

j. Each detector unit shall utilize a /\L = (Delta-L) thresholding

technique to provide a more constant, predictable vehicle

detection sensitivity with series added inductance, i.e., many

loops connected in series and/or long lead-in/homeruns will

generally require the same sensitivity setting as would be

required for a single loop with short lead-in, to simplify

setup.

k. Each channel shall automatically recover from intermittent

opens or multiple shorts to ground. Each channel shall

tolerate and continue to operate with no change with a single

point short to ground on the loop or lead-in system. Each

channel shall provide a continuous, non-resettable (fail-safe)

output and indication in response to an open loop/open

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lead-in system. The open loop indication and output shall not

be resettable as long as the open exists, except that they shall

be defeated when the channel "Off" position is selected.

l. Extended features shall include: Two serial ports (front panel

RS232 and Edge connector Xmit/Recve), TS1 and TS2

compatible from manual or software switch, microloop

occupancy detection, Traffic counting capable to include

long-loop presence count from 15 minute to infinite intervals

all accessible from either serial interface, Dual Detect and

Fault LED indicators per channel, External inputs to control

Timing functions and enable Remote Reset, Extended

diagnostics, programming and Live status available via serial

interface utilizing windows compatible software.

8.6.4 EMERGENCY VEHICLE DETECTORS

OPTIcal COMmunication Detectors for emergency vehicle pre-emption shall be the GTT Model

711, 712 or 722 Optical Detector or approved equal as specified in the construction plan notes.

Placement of the Detectors shall be determined by the Public Works Director. Optical phase

selector modules for emergency vehicle pre-emption shall be GTT Model M752 or approved

equal.

8.6.5 DETECTORS (PEDESTRIAN PUSH-BUTTON)

8.6.5.1. General

a. Pedestrian push-buttons shall be of the direct push-button

contact type. They shall operate on a voltage not to exceed

18 volts AC. They shall be of tamper-proof design and

equipped with a push-button instruction sign as shown in the

Standard Details.

b. The assembly shall be weatherproof.

c. The housing shall be shaped to fit the curvature of the pole to

which it is attached to provide a rigid installation. Saddles

shall be provided to make a neat fit when required.

Pedestrian signs shall be installed as shown on the Standard

Details.

d. At all times, detector standards must comply with current

ADA codes and requirements.

8.6.6 TRAFFIC SIGNAL POLES, PEDESTALS AND MAST ARMS

Traffic signal poles, pedestals and mast arms shall be of the general configuration shown on

standard drawings. All traffic signal poles and mast arms shall be designed to meet the

requirements outlined in the latest edition of "Standard Specifications for Structural Supports for

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Highway Signs, Luminaries, and Traffic Signals," published by AASHTO, for a wind velocity of

90 mph.

8.6.7 CONTROLLER CABINET

8.6.7.1. General

a. All controllers and auxiliary equipment shall be housed in a

factory wired, weatherproof, metal cabinet following NEMA

specification TS2 type 2. The cabinet shall be of sufficient

size to accommodate all equipment as approved by the Public

Works Director.

b. The cabinet shall be constructed of 0.125 minimum thickness

bare aluminum. Cabinets shall be braced internally or by

folded seams in order to provide sufficient rigidity to

withstand normal handling and transport to the field location

without deforming.

c. The main door shall have a self locking, keyed, tumbler lock

with two keys. Hinges shall be mounted on the cabinet in

such a way that interchange-ability of doors is possible

between cabinets of like size and manufacturer. Hinge pins

shall be stainless steel. Doors shall have neoprene gaskets of

sufficient thickness to provide a rain tight and dust tight seal.

d. The engineer will provide, during the construction period, an

additional external lock for the controller cabinet to maintain

security of the controller cabinet.

e. A police or auxiliary door shall be provided. It shall be

constructed so that no sharp edges protrude from the main

door and shall provide access to a panel with labeled

switches for automatic to flashing operation and signal power

on/off.

f. The cabinet shall be equipped with a thermostatically

controlled, ball bearing fan with a capability of at least 100

cubic feet per minute. The fan shall be mounted in a

weatherproof housing attached to the top of the cabinet. The

thermostat shall be adjustable to turn on between 90o F and

150o F and be so mounted as to be easily accessible for

adjustment from the front of the cabinet. An internally

mounted incandescent lamp socket shall be provided with

150 watt capability and switched "on" only when the main

door is open.

g. The cabinet shall have two shelves each capable of

supporting 75 pounds. Shelves shall be supported on

brackets which provide for height adjustments. Each cabinet

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shall contain a 10 mil thick plastic envelope with side

opening. It shall be a minimum size of 10" x 12" and be

attached to the door by screws.

h. Assembly wiring - All cabinet wiring shall be neatly arranged

and laced or enclosed in plastic tubing. No harness or wire

shall be attached to any shelf rack or other point where it may

be damaged by movement of shelves or doors.

i. Terminal Facilities - Terminal facilities (load bays) shall be

firmly attached in a position not less than 6 inches from the

bottom of the cabinet so as to provide easy access and

maximum convenience to the user.

j. Side mounted auxiliary panels should be firmly installed with

the forward edge not more than 4 inches from the door sill

and not less than 6 inches from the bottom of the cabinet in

all cabinets.

k. The load bay and it's associated equipment, harness,

switches, etc., shall be grouped on removable panels. Each

panel or group of receptacles and connecting cables shall be

arranged to permit so that work can be performed on panel

backs or cables.

l. A load switch bay and flash transfer capability is required for

each phase. Load switches shall be provided for only the

phases shown on the plans.

m. The load bay shall be protected by a main circuit breaker. A

gas tube surge arrester with MOV and a suitable radio

interference filter shall be supplied. The arrester shall be a

three electrode type with the following ratings:

1) Impulse Breakdown - less than 1,000 volts in less

than .1 microseconds at 10 KV per micro-second.

2) Standby Current - less than 1 milliampere

3) Striking Voltage - greater than 212 VDC

4) Energy Capability - capable of withstanding pulses

of peak current each of which will rise in 8

microseconds and fall in 20 micro-seconds to

one-half the peak voltage at 3 minute intervals.

5) Peak Current Ratings shall be 20,000 amps. The

MOV shall have ratings equal to or better than a

General Electric type VI50LA20A. The RFI filter

shall have a current rating equal to or greater than the

main circuit breaker capacity.

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n. Field terminals shall be screw type, capable of

accommodating at least three number 12AWG wires. All

terminals in the load bay shall be permanently identified by

engraving, silk screening or contrasting plastic labels.

Terminal blocks shall be the barrier type and no live parts

shall extend above the barrier.

o. A convenience outlet with a ground fault interrupter fused at

15 amps shall be provided. It should be located in a position

which is convenient and safe for service personnel.

p. All AC power busses, switch or relay lugs and/or similar

activity connection points which extend more than 1-1/2

inches from the panel are to be protected by insulation for

safety. The locations of these items shall provide reasonable

protection for service personnel.

q. Signal power relays shall be mercury wetted, equal to or

greater than circuit breaker capacity. Flash transfer relays

shall be as manufactured by Midtex Model 136-62 T 3A1,

120 VAC, DPDT, 30 amp with Jones Plug base and dust

cover or approved equal.

r. Flasher. The cabinet shall be equipped for flashing operation

of signal lights with a 2 circuit solid state flasher in

accordance with the latest NEMA specifications (15 amps

per circuit). Flashing operation shall be set for flashing

yellow on all main street approaches and red on all other

approaches. Pedestrian and turn signals shall be extinguished

during flashing operation. The flashing mechanism shall

remain in operation during shutdown or removal of

controller.

s. Load Switches. The cabinet shall be equipped with solid

state load switching assemblies in accordance with the latest

NEMA specification. Each load switch to be equipped with a

3 input LED indicator. Load switches shall contain 3

separate cube type solid state relays, which use a solid state

switch which is capable of operations at 240 VAC and 25

amps when properly heat sinked but derated to 10 amps when

used in load pack assembly.

t. Conflict Monitor. The cabinet shall have provision for

conflict prevention in accordance with the latest NEMA TS2

specification. Conflict prevention shall be provided by a

conflicting display monitor unit that monitors all green,

yellow and walk displays and detects absence of reds to

cause flashing operation and stop timing if conflicting

indications are detected. Removal of the monitor from the

cabinet shall cause flashing operation. Conflict monitors

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shall be as manufactured by Eberly Designs, 12 LEP or

approved equal.

u. Emergency Vehicle Preemption. The cabinet shall be

equipped and wired with an Opticom Card rack mount for

3M Model 562 or approved equal. All equipment shall be

capable of accommodating a minimum of two modules with

capability of four-channel operation.

8.6.8 ACTUATED CONTROLLERS

8.6.8.1. General

a. Compatibility - THE LOCAL CONTROLLER AND

CABINET SHALL BE 100% COMPATIBLE WITH THE

CITY OF NORTHGLENN'S EXISTING COMPUTERIZED

SIGNAL SYSTEM WHICH UTILIZES ECONOLITE

EQUIPMENT OR NECESSARY MODIFICATIONS OF

THE SOFTWARE AND HARDWARE SHALL BE

INCLUDED TO MAKE BOTH SYSTEMS FULLY

COMPATIBLE.

b. An actuated controller shall be completely solid state,

electronic device capable of selecting and timing traffic

movements. It shall provide timing and load switch control

of each major vehicular phase, including concurrent

associated pedestrian movements. The controller shall

conform to the latest NEMA specifications and shall provide

for complete and full operation of eight phases from within

either a TS1 or TS2 type 1 cabinet.

c. The controller shall have all electronic components easily

accessible and arranged in functional groupings on the

printed circuit boards. Printed circuit boards shall be

designed to facilitate identification of components for

maintenance purposes. Printed circuit design shall be of

NEMA specification quality and designed so that

components may be removed and replaced without

permanent damage to the board or track.

d. Timing shall be adjustable on the controller face by keyboard

programming. A security code or other means shall be

provided to prevent unauthorized or accidental entry.

e. Timing shall be readable from a display which is sufficient to

make certain that all register positions can be easily and

definitely recalled. Every keyboard controller shall have an

easily followed legend silk screened on the face of the

controller or on a metal or plastic card or placard which is

securely attached by screws or rivets.

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f. All circuitry components shall be available on the open

market and the original manufacturer's part number shall be

shown on the part's list.

g. Overlap programming shall be provided by NEMA standard

overlap board and/or keyboard.

h. An entry mode to any single phase parameter of a keyboard

controller shall not affect any other parameter or the same

parameter on another phase, unless programmed by specific

keyboard instructions, such as, "copy" sequences or other

prescribed methods of rapid program entry.

i. Every controller supplied shall be the manufacturer's latest,

first line production model tested and delivered by a domestic

manufacturer who is regularly engaged in the construction of

such equipment.

j. Each controller shall be supplied with a complete set of

operational and service manuals, wiring schematics and part's

layout up to a maximum of ten sets per order. Any controller

for which these documents are not available is not a

production model within the meaning of these specifications.

k. Each controller shall have a removable data module.

l. Pre-emption. All actuated controllers shall be equipped to

accommodate four E.V.P. inputs and one railroad preemption

input.

8.6.8.2. Coordination Unit

a. The coordination unit shall be an internal function within

each local controller and shall meet, as a minimum, the

following functional requirements.

b. The coordinator shall provide for at least four cycle lengths

adjustable from 30 to 255 seconds, three offsets adjustable

from 0 to 99 percent with offset correction by dwelling in

coordinated phase or smooth transition, and four splits per

cycle.

c. Standard NEMA functions shall be used to control the

intersection timing.

d. The coordinator shall be capable of changing the controller's

phase sequence upon command and telemetry failure.

e. The coordinator shall be capable of setting the intersection

free by loss of system sync, cycle/offset false commands, free

command and telemetry failure.

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f. The coordinator shall be capable of setting the intersection

into a flashing operation in accordance with the Manual on

Uniform Traffic Control Devices, latest edition.

g. The coordinator shall be capable to operate with telemetry

module without additional hardware or software.

h. Time-base coordination mode shall be provided as a backup

with all standard coordination features available. At least

two 7-day programs shall be available with at least 36

additional holiday programs in the event of a master

controller or communications failure. Time-base standby

mode shall be programmable for an entire year with

automatic daylight savings and leap-year changes.

8.6.8.3. System Telemetry

a. Telemetry equipment shall be an internal plug-in module to a

local controller with easy access for removal. Master

controller or stand-alone chassis may contain standard

plug-in module. Each telemetry unit shall be capable of

transmitting data to and from local controller, local detectors

and system detectors (8 per intersection). A provision shall

be made to reject invalid messages. The system command

shall be transferred each second to maintain time sync.

b. The telemetry equipment shall be designed so that all

communications among intersections in one system can be

accomplished over no more than two pairs of hard wire

interconnect or leased phone lines. Dedicated pairs from the

master to each local intersection are not permitted.

8.6.9 ON-STREET MASTER

8.6.9.1. General

a. Cabinet Assembly - The master controller shall be wired into

a cabinet assembly which also includes a local intersection

equipment configuration. The cabinet shall be wired

complete with master connecting cables in accordance with

applicable portions of the local controller cabinet

specifications. The incoming power service and interconnect

terminals shall be adequately equipped with surge arrestors to

protect against high energy transients.

b. Incoming Sensor Data - The master shall have the ability to

receive output data from at least eight sensors from each

local intersection. It shall be possible to assign at least 32 of

the incoming sensors to internal computational channels for

pattern selection analysis.

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c. Traffic Pattern Selection. The program-in-effect shall be

selected on a priority basis with the following priority

arrangements:

1) Manual entry from keyboard

2) External command from a master

3) Time-of-day/day-of-week schedule

4) Traffic responsive -based on sampling sensor

analysis

d. The master shall select one of six different cycle lengths or

"free" operation based on inbound or outbound volume

levels. It shall be possible to program segments in the

volume range levels to change to the next higher or lower

cycle lengths.

e. The master shall be able to select any of five different offset

plans per cycle. Offset plans shall be chosen based on the

differential between inbound and outbound volume levels.

The five offset plans shall be designated as follows:

1) Heavy inbound

2) Inbound

3) Average

4) Outbound

5) Heavy outbound

f. When balanced flow occurs, the master shall select the

Average Offset plan. When the volume in one direction

exceeds the volume in the other direction by the programmed

amount, a standard preferential offset shall be implemented.

If the volume differential exceeds a second (higher)

programmed amount, a heavy preferential offset must be

implemented. It shall also be possible to reserve the heavy

preferential offset plans for special pattern implementation

only. Programmable settings must be provided for both

entering and leaving each offset.

g. Split plan selection shall be identical to offset plan selection

except that arterial traffic volume levels must be compared to

side street volume levels. Three different split plans shall be

provided:

1) Heavy arterial

2) Average

3) Heavy side street

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h. The master shall call for the average split plan during normal

conditions. If the arterial volume exceeds the side street

volume by the programmed amount, the heavy arterial split

shall be selected. In the same manner, if side street volume

exceeds arterial volume by a programmed amount, the heavy

side street split shall be called.

i. Crossing Artery Synchronization - The master controller

shall have capability to coordinate with a separate master

controller of the crossing artery through the common

intersection for both systems.

j. System Diagnostics - Diagnostic tests shall be performed on

system detectors, telemetry communications and intersection

operation.

k. Sampling sensors shall be monitored for absence of calls or

constant calls. If a sensor fails, it shall be automatically

disconnected from the calculations for traffic responsive plan

selection. If normal sensor operation resumes, the sensor

shall be automatically reinstated.

l. Telemetry communications diagnostics shall monitor

readbacks for no response condition including local telemetry

and telemetry channels.

m. Intersection diagnostics shall be available to display

intersection status condition. All fault conditions shall be

reported and logged.

n. Count storage - The master shall have the ability to tabulate

and store 15 minute count data from up to 32 different

sensors. The data shall be available for automatic transfer to

the central office facility upon request.

o. The selection of the sensors to be counted in any 24 hour

period shall be completely programmable from the central

office computer.

p. Miscellaneous Data Storage. The master shall store all of

the following data:

1) The time of day and location of all sampling sensor

failures. If normal operation resumes, this time shall

also be recorded.

2) The time of day, location and mode of all local

intersection failures. The time that normal operation

resumes must also be recorded.

3) The time and mode of all pattern changes. Changes

due to external override must be distinguished from

normal pattern changes.

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4) The average volume or occupancy level for each 15

minute period for all computational channels.

q. It shall be possible to transmit any of the data listed above to

the central office computer automatically or upon demand.

r. Downloading Local Coordination Settings. It shall be

possible to download any local intersection coordination

setting (offset, force off or permissive period) from the

master via the unit's keyboard.

s. Display. During normal operation, the timing patter in effect

shall be displayed on the front panel, including the cycle,

offset plan and split plans selected. Also, the unit shall

indicate how the timing plan was selected - through normal

volume calculations, by an occupancy channel or by manual

or central computer override. The master shall also indicate

when the time of day mode is in effect and show whether this

mode was selected manually or because of sensor failures.

t. External Override. The master controller shall have

appropriate inputs to externally select any timing pattern and

override the pattern selected through traffic analysis.

u. Telemetry. The master shall include a telemetry module for

two way communications between the master and local

controllers. The equipment shall be compatible with the

telemetry equipment specified for the local controllers

8.6.10 MISCELLANEOUS HARDWARE

8.6.10.1. General

a. Aluminum pedestal mounts (Type III) shall be either of two

(2) types, as called for in the plans and specifications. Center

mount with two (2) side ports, plain or offset mount serrated

with one (1) side port.

b. Covers for water valve pull boxes shall have the word

"Traffic" cast into them to avoid confusion with a water

department pull box.

c. Mast arm brackets shall be Astro brackets or City approved

equivalent and shall be installed 90 degrees to the roadway.

8.6.11 PAINT - SIGNAL POLES

8.6.11.1. New Structures

a. All new signal poles and mastarms shall be factory painted

with an epoxy primer and Polyurethane top coat liquid

coating. Surface preparation shall be blast cleaned to Steel

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Structure Painting Council Surface Preparation Specification

No. 6 (SSPC-SP6) requirement utilizing cast steel abrasives

conforming to the Society of Automotive Engineers (SAE)

Recommended Practice J827.

b. All accessible interior surfaces shall be coated with a lead

and chromate free red oxide rust inhibitive alkyd primer to a

minimum dry film thickness of 1.0 mils.

c. All exterior surfaces shall be coated with a rust-inhibitive

Epoxy-Polyamide Primer to a minimum dry film thickness of

2.0 mils. The top coat shall consist of one coat of

Semi-Gloss High-Build Acrylic Polyurethane Enamel,

Tnemec Endura Shield or approved equal, to a minimum dry

film thickness of 2.0 mils. The top coat color shall be

Federal Green No. 34108.

d. Any surface areas damaged during handling or installation

shall be repaired immediately with a spot coat of epoxy

primer and a polyurethane finish as specified above. The

paint manufacturer's application instructions shall be

followed.

e. The City will consider galvanized poles with painted top coat

for improved rust protection as specified above and

according to manufacturers painting recommendations.

8.6.11.2. Existing Structures

a. All designated previously installed signal poles and mast

arms shall be field painted. All exterior surfaces shall be

cleaned and examined for damaged paint, and any such

damage shall be given a spot coat of primer and the entire

exterior surface re-painted. Previously painted surfaces

whether finish or prime coats, shall be scuff sanded to yield

500 PSI of adhesion with particular attention paid to the

lower eight feet (8') of the pole. Inspection of the poles prior

to application of the finish coat is required.

b. A finish coat of Sherwin Williams DTM (Direct to Metal)

Acrylic Gloss or approved equal shall be applied over the

primer or previously painted surfaces. Two coatings shall be

applied leaving approximately 6 mils of dry film. The color

shall be a dark green formula (Federal Green No. 34108).

c. The painting shall be done in a neat and workmanlike manner

and may be applied either by hand brushing or spraying. The

engineer reserves the right to require the use of brushes for

the application of paint should the work done by the paint

spraying machine prove unsatisfactory or objectionable.

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d. All designated traffic and pedestrian signal heads shall be

painted flat black unless otherwise specified.

8.6.12 INSTRUCTIONS AND WIRING DIAGRAMS

All equipment shall be provided with three sets of complete installation instructions, including a

complete chart of field connections as well as a manual for the controller, containing service

instructions, wiring diagrams, trouble-shooting procedures, etc. Each and every component used

shall be clearly referenced in the service manual and its value, ratings and manufacturer part

number shall be given.

8.6.13 GUARANTEE

The contractor shall include in his proposal all warrants and/or guarantees with respect to

materials, parts, workmanship and performance of the product to be supplied. The minimum

guarantee period for the product shall be two (2) years from the date of final acceptance of the

contract. The contractor shall attach to the bid a statement that all material to be supplied is

either in exact accordance with the specifications or shall list in detail any and all deviations

therefrom. The supplying of equipment that is not in accord with the specification and on which

the contractor has indicated no exception shall be cause for rejection of the equipment and

correction of the non-specification items entirely at the contractor's expense.

8.6.14 SIGN SPECIFICATIONS

8.6.14.1. Sign Face Materials

All stop signs, yield signs, and "Do Not Enter" sign faces shall be fabricated from

Scotchlite reflective sheeting, high-intensity grade or approved equal. All other sign

faces shall be fabricated from Scotchlite reflective sheeting, engineer grade or approved

equal.

8.6.14.2. Sign Post Materials

All sign posts shall be fabricated from 12-gauge galvanized, perforated Telespar tubing

or approved equal. The sign post assembly shall consist of a VLOC steel 2 foot anchor

sleeve and a two inch by two inch by ten-foot (2" x 2" x 10') post. See detailed drawing

in Appendix.

8.6.14.3. Fire Lane Sign Specifications

Size: 12 Inches by 18 Inches

Materials: Per Current MTCD standards at time of installation.

Colors: Sign Letters on White Background. The letter on the symbol sign

shall be black.

Wording: "No Parking" (or)

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"Fire Lane" (with appropriate arrow)

General: Letter size, border, hole locations, and corner radii shall be per the

Manual on Uniform Traffic Control Devices specifications.

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